Die-to-die isolation structures for packaged transistor devices

Abstract

A transistor amplifier package includes a base, one or more transistor dies on the base, first and second leads coupled to the one or more transistor dies and defining respective radio frequency (RF) signal paths, and an isolation structure on the base between the respective RF signal paths. The isolation structure includes first and second wire bonds. The first and second wire bonds may have a crossed configuration defining at least one cross point therebetween. Related wire bond-based isolation structures are also discussed.

What is claimed is: 
     
       1. A transistor amplifier package, comprising:
 a base; 
 one or more transistor dies on the base; 
 first and second leads coupled to the one or more transistor dies, wherein the first and second leads define respective radio frequency (RF) signal paths; and 
 an isolation structure between the respective RF signal paths, the isolation structure comprising first and second wire bonds in a crossed configuration defining at least one cross point therebetween. 
 
     
     
       2. The transistor amplifier package of  claim 1 , wherein the base comprises a conductive element that is configured to provide an electrical ground for the one or more transistor dies, and wherein the first and second wire bonds are coupled to the conductive element and/or to respective bond pads that are electrically connected to the conductive element. 
     
     
       3. The transistor amplifier package of  claim 2 , wherein the isolation structure comprises a plurality of crossed wire bond structures arranged in one or more dimensions between the respective RF signal paths, wherein a respective one of the crossed wire bond structures comprises the first and second wire bonds in the crossed configuration. 
     
     
       4. The transistor amplifier package of  claim 3 , wherein at least one of the first and second wire bonds comprises a plurality of wire bonds, such that the first and/or second wire bonds cross two or more of the plurality of wire bonds. 
     
     
       5. The transistor amplifier package of  claim 2 , wherein the respective bond pads include bond pads on a surface of the one or more transistor dies and/or bond pads on a surface of one or more passive devices on the base. 
     
     
       6. The transistor amplifier package of  claim 2 , wherein the isolation structure continuously extends between the respective RF signal paths, and wherein the first and second wire bonds define multiple cross points therebetween. 
     
     
       7. The transistor amplifier package of  claim 2 , wherein the respective RF signal paths comprise first and second RF amplifier paths, wherein the first and second leads comprise first and second input leads or first and second output leads of the first and second RF amplifier paths, respectively, and wherein the one or more transistor dies comprises first and second transistor dies coupled to the first and second leads, respectively. 
     
     
       8. The transistor amplifier package of  claim 7 , wherein the first and second wire bonds are coupled to the respective bond pads, wherein the respective bond pads include bond pads that are on the first and second transistor dies of the first and second RF amplifier paths and/or bond pads that are on respective passive devices coupled to the first and second transistor dies. 
     
     
       9. The transistor amplifier package of  claim 7 , wherein the conductive element comprises a ground connection lead between the first and second input leads or between the first and second output leads. 
     
     
       10. The transistor amplifier package of  claim 7 , wherein the conductive element comprises a surface of the base including the one or more transistor dies thereon, and wherein the base is free of a ground connection lead. 
     
     
       11. The transistor amplifier package of  claim 7 , wherein the isolation structure comprises a first isolation structure between the first and second RF amplifier paths, and further comprising:
 a second isolation structure on at least one of the first and second transistor dies between input and output RF signal paths of a corresponding one of the first and second RF amplifier paths, the second isolation structure comprising respective wire bonds in a linear or crossed configuration. 
 
     
     
       12. The transistor amplifier package of  claim 2 , wherein the respective RF signal paths comprise input and output RF signal paths of a RF amplifier path, wherein the first and second leads comprise input and output leads of the RF amplifier path, respectively, and wherein the one or more transistor dies comprises a first transistor die coupled between the input and output leads. 
     
     
       13. The transistor amplifier package of  claim 12 , wherein the respective bond pads are on a surface of the first transistor die, and wherein each of the first and second wire bonds is coupled to multiple of the respective bond pads. 
     
     
       14. The transistor amplifier package of  claim 1 , wherein the first and second wire bonds are separated from one another by less than 5 mils. 
     
     
       15. The transistor amplifier package of  claim 14 , wherein, at a cross point between the first and second wire bonds, the first and second wire bonds are separated from one another by about 2 mils or less. 
     
     
       16. The transistor amplifier package of  claim 15 , wherein respective loop heights of the first and second wire bonds from the base are at least a height of the one or more transistor dies from the base. 
     
     
       17. The transistor amplifier package of  claim 1 , wherein respective loop heights of the first and second wire bonds from the base are different. 
     
     
       18. The transistor amplifier package of  claim 1 , wherein the one or more transistor dies comprise a gallium nitride-based high electron mobility transistor (HEMT). 
     
     
       19. The transistor amplifier package of  claim 1 , wherein the one or more transistor dies comprise a silicon-based laterally diffused metal oxide semiconductor (LDMOS) transistor. 
     
     
       20. The transistor amplifier package of  claim 1 , wherein the one or more transistor dies are configured to operate in at least a portion of one or more of 0.6-1 GHz, 1.4-1.6 GHz, 1.7-1.9 GHz, 1.8-2.2 GHz, 2.3-2.7 GHz, 3.3-4.2 GHz, 4.4-5.0 GHz, or 5.1-6.0 GHz frequency bands. 
     
     
       21. The transistor amplifier package of  claim 1 , wherein the one or more transistor dies are configured to operate at frequencies above 10 GHz. 
     
     
       22. The transistor amplifier package of  claim 1 , further comprising:
 a housing comprising a ceramic lid that defines an air cavity around the one or more transistor dies. 
 
     
     
       23. The transistor amplifier package of  claim 1 , further comprising:
 a housing comprising a plastic overmold that encapsulates the one or more transistor dies. 
 
     
     
       24. A transistor amplifier package, comprising:
 a base; 
 one or more transistor dies on the base; 
 first and second leads coupled to the one or more transistor dies, wherein the first and second leads define respective radio frequency (RF) signal paths; and 
 an isolation structure between the respective RF signal paths, the isolation structure comprising first and second wire bonds that are separated from one another by less than about 5 mils. 
 
     
     
       25. A transistor amplifier package, comprising:
 a base; 
 one or more transistor dies on the base; 
 first and second leads coupled to the one or more transistor dies, wherein the first and second leads define respective radio frequency (RF) signal paths; and 
 an isolation structure between the respective RF signal paths, the isolation structure comprising first and second wire bonds in a non-linear configuration coupled to the base and/or to the one or more transistor dies. 
 
     
     
       26. A transistor amplifier package, comprising:
 a base; 
 a transistor die on the base; 
 input and output leads coupled to the transistor die, wherein the input and output leads define input and output radio frequency (RF) signal paths, respectively, of a RF amplifier path; and 
 an isolation structure between the input and output RF signal paths, the isolation structure comprising first and second wire bonds coupled to the base and/or to respective bond pads of the transistor die. 
 
     
     
       27. The transistor amplifier package of  claim 24 , wherein the first and second wire bonds have a crossed configuration defining at least one cross point therebetween. 
     
     
       28. The transistor amplifier package of  claim 27 , wherein, at the at least one cross point, the first and second wire bonds are separated from one another by about 2 mils or less. 
     
     
       29. The transistor amplifier package of  claim 24 , wherein the isolation structure continuously extends between the respective RF signal paths, and the first and second wire bonds define multiple cross points therebetween. 
     
     
       30. The transistor amplifier package of  claim 25 , wherein the base comprises a conductive layer that is configured to provide an electrical ground, and wherein the first and second wire bonds are coupled to respective bond pads of the one or more transistor dies that are electrically connected to the conductive layer. 
     
     
       31. The transistor amplifier package of  claim 30 , wherein the first and second wire bonds have a crossed configuration defining at least one cross point therebetween. 
     
     
       32. The transistor amplifier package of  claim 31 , wherein each of the first and second wire bonds is coupled between the conductive layer of the base and a respective one of the bond pads of the first or second transistor dies. 
     
     
       33. The transistor amplifier package of  claim 31 , wherein each of the first and second wire bonds is coupled between a respective one of the bond pads of the first transistor die and a respective one of the bond pads of the second transistor die. 
     
     
       34. The transistor amplifier package of  claim 26 , wherein the base comprises a conductive layer that is configured to provide an electrical ground, and wherein the respective bond pads of the transistor die are electrically connected to the conductive layer. 
     
     
       35. The transistor amplifier package of  claim 34 , wherein the first and second wire bonds extend parallel to one another in a linear configuration between the input and output RF signal paths. 
     
     
       36. The transistor amplifier package of  claim 34 , wherein the first and second wire bonds have a crossed configuration defining at least one cross point between the input and output RF signal paths.